This is where BeamRacer gets deactivated - Githubissues

ytmytm / geos

Source code of GEOS 2.0 for the Commodore 64 and 128

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This is where BeamRacer gets deactivated #1

Closed ytmytm closed 3 years ago

ytmytm commented 3 years ago

https://github.com/ytmytm/geos/blob/624b12301b37ac312aa108f355e8ed1be728e2d7/kernal/dlgbox/dlgbox1d.s#L91

because of high-nibble (6th bit in particular) of $d02e (mob7clr == mob1clr+7) set to 1

https://github.com/madhackerslab/beamracer-vbasic/blob/3c4228236e11f1b0f09af5bde7f739ef31f8e3f2/basic.s#L1671

and

https://github.com/abbruzze/kernal64/blob/9c83299b264f0e25186b807e3b888f2daccb7301/Kernal64/src/ucesoft/cbm/peripheral/vic/coprocessor/VASYL.scala#L421

Options:

special case to clear high nibble of sprite colors on read
special case to clear high nibble of sprite colors on write
don't save 7th sprite color (who uses non-system sprites with GEOS? GeoBASIC? desk accesory games?)
don't save sprite colors at all

This should fix the issue and 624b12301b37ac312aa108f355e8ed1be728e2d7 can be reverted

ytmytm commented 3 years ago

silverdr confirms that setting 6th bit of mob7clr to 1 un-knocks VASYL